﻿//1.修改程序清单10.7的rain.c程序，用指针进行计算（仍然要声明并初始 化数组）。
#include <stdio.h>
#define MONTHS 12 
#define YEARS 5
int main(void) {
    const float rain[YEARS][MONTHS] = {
        {4.3,4.3,4.3,3.0,2.0,1.2,0.2,0.2,0.4,2.4,3.5,6.6},
        {8.5,8.2,1.2,1.6,2.4,0.0,5.2,0.9,0.3,0.9,1.4,7.3},
        {9.1,8.5,6.7,4.3,2.1,0.8,0.2,0.2,1.1,2.3,6.1,8.4},
        {7.2,9.9,8.4,3.3,1.2,0.8,0.4,0.0,0.6,1.7,4.3,6.2},
        {7.6,5.6,3.8,2.8,3.8,0.2,0.0,0.0,0.0,1.3,2.6,5.2}
    };
    int year, month;
    float subtot, total;
    printf("YEAR    RAINFALL  (inches)\n");
    for (year = 0, total = 0; year < YEARS; year++) {
        for (month = 0, subtot = 0; month < MONTHS; month++) {
            subtot += *(*(rain + year) + month);
        }
        printf("%5d %15.1f\n", 2010 + year, subtot);        
        total += subtot;
    }
    printf("\nThe yearly average is %.1f inches.\n\n", total / YEARS);   
    printf("MONTHLY AVERAGES:\n\n");   
    printf(" Jan  Feb  Mar  Apr  May  Jun  Jul  Aug  Sep  Oct ");   
    printf(" Nov  Dec\n");
    for (month = 0; month < MONTHS; month++) {                 
        for (year = 0, subtot = 0; year < YEARS; year++)         
            subtot += *(*(rain + year) + month);       
        printf("%4.1f ", subtot / YEARS); }    
    printf("\n");  
    return 0;
}